“To raise people’s auto insurance premium because they can’t afford to buy their homes unfairly discriminates against lower-income drivers,” said J. Robert Hunter, the Consumer Federation of America’s insurance director and the former Insurance Commissioner of Texas. “A good driver is a good driver whether she rents or owns her home. Insurance companies should not be allowed to target people based on home ownership status.”

A difference does not show up with all insurers or in all cities. The difference in Oakland, for instance, is zero because California law does not allow it, the consumer group says. Geico happens not to charge renters differently across the board, officials said.

But nationally, based on quotes for a 30-year old safe driver, the consumer federation found that premiums averaged about $112 more, or 7 percent higher, per year for renters. In a 10-city sampling including Tampa, Liberty Mutual penalized renters the most at $307 per year, or 19 percent more.

CFA officials maintain this is one of several ways insurers discriminate with a backdoor method to set higher rates for lower-income or minority drivers. Median income of renters in the U.S. was $27,800 in 2013 compared with $63,400 for homeowners, officials said.

On the other side of the issue, a consumer with a good driving record who owns a home might not think this is terrible system, if it results in rates that seem fairer to her.

Industry groups say consumers benefit when insurers have the flexibility to set prices that vary in the marketplace, as opposed to one-size-fits-all rates.

Insurers have “found over time home owners are less likely to get into an accident,” said Jim Lynch, chief actuary of the industry-funded Insurance Information Institute. “That’s reflected in the rates.”